A device for curtailing electric demand is suitable as a tool for responding to the real-time pricing of electrical energy or for reducing demand during power shortages. The device (104) according to the present invention works in conjunction with an energy management system (40), which receives demand signals from an electric meter (24). Upon executing a curtailment command sent to the device (104) through a communications network (48, 50, 102), device intercepts and biases the signal going to the energy management system (40), which, in effect, coerces it to reduce the demand upon the meter (24) and upon the electric grid (20).